diff --git a/HrynCo.NotificationService.Web/Controllers/Admin/AdminChannelsController.cs b/HrynCo.NotificationService.Web/Controllers/Admin/AdminChannelsController.cs
index 4aa3718..d05585d 100644
--- a/HrynCo.NotificationService.Web/Controllers/Admin/AdminChannelsController.cs
+++ b/HrynCo.NotificationService.Web/Controllers/Admin/AdminChannelsController.cs
@@ -163,7 +163,11 @@ public class AdminChannelsController : Controller
             };
 
             using var client = new SmtpClient();
-            var secureSocket = smtp.UseSsl ? SecureSocketOptions.SslOnConnect : SecureSocketOptions.StartTlsWhenAvailable;
+            var secureSocket = smtp.Port == 465
+                ? SecureSocketOptions.SslOnConnect
+                : smtp.UseSsl
+                    ? SecureSocketOptions.StartTls
+                    : SecureSocketOptions.None;
             await client.ConnectAsync(smtp.Host, smtp.Port, secureSocket, ct);
 
             if (!string.IsNullOrWhiteSpace(smtp.Username))